Tried everything, this is only for my phone app, I can log into the browser perfectly fine. However, since you can only post items through the app, it's pretty important that the app works. Anyways, after 2 weeks of hampering the OfferUp support, this is the resolution that I got.
"At this time, out Tech Support team is working on resolving this issue.
Your account is included in the list of accounts that have been affected."